Essential Role of P-Selectin in the Initiation of the Inflammatory Response Induced by Hemorrhage and Reinfusion

Resuscitation from hemorrhage induces profound pathophysiologic alterations and activates inflammatory cascades able to initiate neutrophil accumulation in a variety of tissues. This process is accompanied by acute organ damage (e.g., lungs and liver). We have previously demonstrated that significant leukocyte–endothelium interactions occur very early in other forms of ischemia/reperfusion (i.e., splanchnic ischemia/reperfusion and traumatic shock) which are largely mediated by increased expression of the adhesion molecule, P-selectin, on the vascular endothelium. Here we postulated that increased endothelial expression of P-selectin in the microvasculature would play an essential role in initiating the inflammatory signaling of hemorrhagic shock. Using intravital microscopy, we found that hemorrhagic shock significantly increased the number of rolling and adherent leukocytes in the mouse splanchnic microcirculation. In contrast, mice genetically deficient in P-selectin, or wild-type mice given either an anti–P-selectin monoclonal antibody or a recombinant soluble P-selectin glycoprotein ligand (PSGL)-1 immunoglobulin, exhibited markedly attenuated leukocyte–endothelium interaction after hemorrhagic shock. Thus, activation of P-selectin protein on the microvascular endothelium is essential for the initial upregulation of the inflammatory response occurring in hemorrhagic shock. Moreover, endogenous levels of PSGL-1 mRNA were significantly increased in the lung, liver, and small intestine of wild-type mice subjected to hemorrhagic shock. Since PSGL-1 promotes adhesive interactions largely through P-selectin expressed on the vascular endothelium, this result further supports the crucial role played by P-selectin in the recruitment of leukocytes during hemorrhagic shock

Acoustic transfer of protein crystals from agarose pedestals to micromeshes for high-throughput screening

An acoustic high-throughput screening method is described for harvesting protein crystals and combining the protein crystals with chemicals such as a fragment library

Targeting inflammation to reduce cardiovascular disease risk: a realistic clinical prospect?

Data from basic science experiments is overwhelmingly supportive of the causal role of immune-inflammatory response(s) at the core of atherosclerosis, and therefore the theoretical potential to manipulate the inflammatory response to prevent cardiovascular events. However, extrapolation to humans requires care and we still lack definitive evidence to show that interfering in immune-inflammatory processes may safely lessen clinical atherosclerosis. In this review, we discuss key therapeutic targets in the treatment of vascular inflammation, placing basic research in to a wider clinical perspective, as well as identifying outstanding questions

Hitting the target: fragment screening with acoustic in situ co-crystallization of proteins plus fragment libraries on pin-mounted data-collection micromeshes

A method is presented for screening fragment libraries using acoustic droplet ejection to co-crystallize proteins and chemicals directly on micromeshes with as little as 2.5 nl of each component. This method was used to identify previously unreported fragments that bind to lysozyme, thermolysin, and trypsin

Effect of hypercholesterolemia on myocardial function, ischemia-reperfusion injury and cardioprotection by preconditioning, postconditioning and remote conditioning

Hypercholesterolemia is considered to be a principle risk factor for cardiovascular disease, having direct negative effects on the myocardium itself, in addition to the development of atherosclerosis. Since hypercholesterolemia affects global cardiac gene expression profile, among many other factors, increased myocardial oxidative stress, mitochondrial dysfunction and inflammation trigger apoptosis and this may account for myocardial dysfunction and increased susceptibility of the myocardium to infarction. In addition, numerous experimental and clinical studies revealed that hyperlcholesterolemia may interfere with the cardioprotective potential of conditioning mechanisms. Although not fully elucidated, the underlying mechanisms for the lost cardioprotection in hypercholesterolemic animals have been reported to involve dysregulation of eNOS-cGMP, RISK, peroxynitrite-MMP2 signaling pathways, modulation of KATP channels and apoptotic pathways. In this review article, we summarize current knowledge on the effect of hypercholesterolemia on the non-ischemic and ischemic heart as well as on the cardioprotection induced by drugs or ischemic preconditioning (PC), postconditioning (PostC) and remote conditioning. We also summarize the effects of hypercholesterolemia on drug-induced cardioprotection, in the presence of hypercholesterolemia. Future perspectives concerning the mechanisms and the design of pre-clinical and clinical trials are highlighted

In vitro antimicrobial activity of Luffa operculata

INTRODUCTION:Luffa operculata is probably one of the most popular herbal medicines used in the treatment of rhinitis and rhinosinusitis. However, its specific mechanism of action is still unknown.OBJECTIVE: To evaluate in vitro antibacterial activity of L. operculata against three ordinary agents of upper respiratory tract infection: Staphylococcus aureus, Streptococcus pneumoniae and Streptococcus pyogenes.METHODS: Different concentrations of L. operculata alcoholic extract were applied to bacterial broth containing reference and community strains of the three described agents. After a 24-h incubation period, the bacterial culture turbidity was measured. The samples were then inoculated onto Mueller-Hinton and human blood agar plates. Bacterial growth was analyzed after 24- and 48-h incubation period. The test was considered negative when there was no environmental turbidity, confirmed by the absence of bacterial growth into the inoculated plates. Tests were considered positive when either turbidity changes were observed on the bacterial broth or when bacterial growth was detected on inoculated plates. Appropriate statistical analysis of the data was performed.RESULTS:L. operculata extracts showed antibacterial activity mainly to S. pyogenes followed by S. pneumoniae and S. aureus.CONCLUSIONS:L. operculata extract showed promising antibacterial activity in vitro against the studied agents